Distribution of leptospirosis among stray dogs in the Okinawa Islands, Japan: comparison of the microcapsule and microscopic agglutination tests.

Three hundred and thirty-eight sera collected from stray dogs in the Okinawa islands were examined for antibodies against Leptospira interrogans using the microscopic agglutination test (MAT) and the one-point microcapsule agglutination test (MCAT). Seventy-eight sera (23%) showed a positive reaction to at least one of the six serovar antigens, and 69 of these reacted with serovar canicola by microcapsule agglutination test. The mixed microcapsule agglutination test detected 68 of the microscopic agglutination test-positive sera, and the 10 remaining were negative by microcapsule agglutination test. On the other hand, a single microcapsule agglutination test which was sensitized with serovar canicola detected 77 of the microscopic agglutination test-positive sera and the remaining one was microcapsule agglutination test-negative.